Infrastructure needed for jitsi-meet in schools

Dear all,
in this period of time, schools in several Italian provinces are closed. The ministry of Technological innovation is asking public and private companies to help in offering their digital services to allow students to follow lessons remotely.

I was thinking of asking local IT companies their help in setting up a jitsi-meet instance for Southtyrolean Schools (if - hopefully not - they will ever be closed at some time).

The help I need would be to understand what kind of infrastructure we should set-up in our datacenter for the following scenario:

  • 1.000 concurrent classrooms
  • an average of 17 participants for each classroom with one teacher (video/audio) and 16 audio listeners.

A curiosity: how is https://meet.jit.si set-up infrastructurally and how many concurrent users does it support?

Thanks so much in advance for your help.

Best,
Paolo.

3 Likes

Here’s the hammer test results for your consideration:

In short, quad-core Intel ® Xeon® E5-1620 v2 @ 3.70GHz CPU
53 conferences with 5 people. You can do the math.

For load balancing, scenario for schools are simpler. Each classroom has fixed classID,
therefore you can have a reverse proxy to distributes workload to different machines
by the last character of the URL (classID) to make sure all students connected to the same machine and the same session.

You can enable local recording at the teacher’s side, say QuickTime screen recording
for kids who cannot attend class during checks or other reasons.

1 Like

Hi @Paolo_Dongilli,
if you start a conference using the Android app on a smartphone, you can:

  • set a password for that conference
  • send the participation link for that conference to the students
  • the teacher can connect “as a student”, to the session started by the mobile phone, with audio and video ON
  • the students just need to connect to the http link of that class and input the password, with audio and video OFF
  • the teacher could just ask the participants to turn off their cameras AND microphones, at the beginning of the lessons and ask the students to turn their microphones on, only when they are allowed to talk by the teacher.
  • students can raise hands
  • teacher can share his DEKSTOP, or apps, or browser tabs

This would allow you to start testing the conference before you setup a dedicated server: a mobile phone starts the conference, the teacher and the students connect to the conference, which is already running.

Each teacher must start his own conference and send links and passwords to the students

Please notice, @Paolo_Dongilli , that a group of teachers could be in a jitsi conference AND could live stream it using youtube infrastructure: you can livestream a jitsi conference to users that are just “watchers”, using youtube’s infrastructure.

So, if the very limited interaction provided by youtube’s livestreams is enough for you, you can dramatically reduce bandwidth and CPU usage of your server, on your LAN and across your internet connection, by letting youtube stream the conference for you.

That is, two-three-four professors could be making a conference together (just four users) and you could have virtually infinite viewers of that conference, throught youtube’s infrastructure!

Nice, isn’t it?

Hi @shooding, what would the teacher actually do, to do this: should he start a conference through http to the school server that Paolo would setup AND also start quicktime on the desktop he’s using, to record the class lesson?

If not, what would the teacher have to do, in your opinion?

Thank you.

Dear shooding,

we are a group pf High School teachers and we would like to stream in a secure way classes for our kids without external unknown participants for privacy reasons.
My questions as a dummy who is not expert in coding:

  1. is it possible to stream live directly through your webpage to approx. 25 students,
    I mean, just using a normal fiber telecom line from home ?
    Or do we need a dedicated server ?
  2. imagine the kids are no genius either: what should the teacher/they do to start/join the stream ?
  3. is it possible for the teacher to know for sure that the participants are only those intended ? How to do that ?
    We thank you very much in advance for your consideration and we appreciate the time you spend to clarify such very simple issues.
    Yours.

@Paolo_Dongilli @alimortacci is correct.

  • 1 publisher, many watcher: Use YouTube or Jitsi-meet + setup YouTube livestream key +
    YouTube recording (default) if no copyright & privacy concerned
  • 1-to-1 teacher student: Jitsi-meet (perfect P2P) no bandwidth required for server.
  • teacher conferences: Jitsi-meet can help. Not sure “follow-speaker” while recording suits you.
  • 1 publisher, many interactive students: Jitsi-meet, my previous suggestion, record at publisher side with quicktime for best quality & avoid copyright & privacy issue
1 Like
  1. Use password for each room
  2. Jitsi supports automatic downgrade bandwidth if more people joins. The quality goes down as well, so you record the best quality at teacher’s side
  3. Just download Jitsi app from AppStore/GooglePlay. Send kids the classroom URL like
    https://meet.jit.si/MagnificentOrganismsDevourFlatly If they haven’t download app yet. There will be a link to Appstore. If you setup a dedicated server later, there’s a setting part in App let you change URL point to the server.
  4. Teacher (join first, setup password, send kids the link, tell kids to enter their name) teacher can kick outsiders
1 Like

Dear shooding,

thank you very much for your kindness and consideration.
We made a simple trial with Jitsi Meet (just two connections) and we had problems with the videocamera, as it was not possible to activate it or give permission to use it.
We tried Safari, Firefox and Chrome with the same result
Also, we could not find a command to share the screen of the computer, which would be essential for us (math teachers) in order to write notes and equations while on stream.
Do you think we have a way out of these problems ?
Thanks a lot again !
Yours.

We already have an system pre setup for school. If you want to try pls contact me by my email duong.tran@acexis.com and I can setup an demo for you right away.

Have you tried the steps?
https://support.google.com/chrome/answer/2693767?co=GENIE.Platform%3DDesktop&hl=en

Safari won’t work.

Screen sharing button is at the bottom-left, no need for extra chrome extension if you installing the latest version of chrome.

Thanks for the tip, now camera and mic work on Chrome, still unable to use sharing windows.
Chrome is updated: Version 80.0.3987.132 (Official Build) (64-bit)
Where should we see the shared window ?
Are we missing some step ?

Dear shooding,
yes, we found the Share your screen icon in the Jitsi window, we selected it and then we tried the three options, desktop, app, etc… but nothing happened, we could not see the shared desktop, app, etc… anywhere (unless we need some extra step).
Do we miss some extension for Chrome ?
Thank you again for your kind and precious help for dummies.
Yours.

Did you setup a private server or using the official https://meet.jit.si ?
Another easier way for you is:
Download & install the desktop software here:

https://desktop.jitsi.org/Main/Download

It’s based on electron and supports Mac/Windows as well.

we used the official https://meet.jit.si and started videoconferencing from there.
we also downloaded the app but it seems it is no longer anonymous, plus we do not understand the difference between the three protocols prompted to be chosen immediately after opening the app.

If you’re using the official, no chrome extension is required. If nothing prompted when using Chrome, maybe your browser is “blocking pop ups”.

check
chrome://settings/content/popups

The prompted 3 choices are:

  1. Share whatever shown on your screen (privacy)
  2. Share one of your application
  3. Share one of your chrome tab (for slideshow <= my first preference)

Dear shooding,

we are really grateful for your essential and kind help for dummies, the problem was indeed the pop-up block !
Now we have to try the connection with 25 kids.
Do you think commercial 1G fiber speed from teacher’s home and normal speed at the kids’ side would be enough to share a live note writing ?
Yours

2 Likes

Yes it should :slight_smile: Good luck!

You’ll need a good download speed (at least 10 mbps to see all 25 kids at the same time) + normal upload speed (1mbps suggested).
If you used too much bandwidth at the official site server (i’m not sure what’s the limit), then it’s time you need a private server.
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